Lourinhanosaurus
Encyclopedia
Lourinhanosaurus was a carnivorous theropod dinosaur
genus
that lived during the Late Jurassic Period (Kimmeridgian
/Tithonian
). Its first remains were found at Peralta
, near Lourinhã
, Portugal
in 1982, but were not described until 1998, by Portuguese paleontologist Octávio Mateus
.
Its type
(and to date only) species is L. antunesi, in honour of Portuguese paleontologist Miguel Telles Antunes
.
. The holotype
, ML 370, consists of the remains of six cervical vertebrae with six ribs, five sacral vertebrae with ribs, 14 caudal vertebrae, eight chevrons, both femora, right tibia and fibula, one metatarsus, two ilia and both pubes and ischia, as well as an associated 32 gastroliths.
A femur (ML 555) found at Porto das Barcas (Lourinhã Formation
; Late Jurassic) has also been referred to L. antunesi.
Besides these specimens, around 100 eggs (specimen number ML 565), some of them containing embryonic bones, have been found in 1993 at the nearby beach of Paimogo. These were soon assigned to L. antunesi.
Both the skeleton and the eggs are on display at Museu da Lourinhã
.
, it was later discussed as being closely related to Sinraptoridae
, a more inclusive clade within Allosauroidea. Recently, some researchers have been favourable to the idea that L. antunesi is not even an allosauroid, but in fact a member of Megalosauroidea
, a more primitive group of tetanuran
theropods. Benson et al. (2010) found it and Poekilopleuron
to belong to Sinraptoridae
.
Though gastroliths have been found in other theropods since the description of L. antunesi, this was the first theropod dinosaur for which this kind of remains have been assigned. It was concluded during the description that these stones belonged to the animal, and were not swallowed while eating an herbivorous dinosaur.
Dinosaur eggs and embryos, believed to be those of Lourinhanosaurus, have also been discovered; a nest containing more than 100 eggs, some with well-preserved embyros, was announced in 1998.
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
that lived during the Late Jurassic Period (Kimmeridgian
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age or stage in the Late or Upper Jurassic epoch or series. It spans the time between 155.7 ± 4 Ma and 150.8 ± 4 Ma . The Kimmeridgian follows the Oxfordian and precedes the Tithonian....
/Tithonian
Tithonian
In the geologic timescale the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 150.8 ± 4 Ma and 145.5 ± 4 Ma...
). Its first remains were found at Peralta
Peralta
Peralta may refer to:Places:* Peralta, Navarre, village in the South of Navarre, Spain* Peralta, New Mexico, village south of Albuquerque...
, near Lourinhã
Lourinhã
Lourinhã is a municipality in Portugal with a total area of 147.2 km² and a total population of 24,601 inhabitants. The seat of the municipality is the village of Lourinhã, with a population of 8,800 inhabitants....
, Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...
in 1982, but were not described until 1998, by Portuguese paleontologist Octávio Mateus
Octávio Mateus
Octávio Mateus is a Portuguese dinosaur paleontologist and biologist . He received his PhD at Universidade Nova de Lisboa in 2005...
.
Its type
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
(and to date only) species is L. antunesi, in honour of Portuguese paleontologist Miguel Telles Antunes
Miguel Telles Antunes
Miguel Telles Antunes is a Portuguese palaeontologist. He is specializes, among other things, in dinosaur palaeontology.Antunes is the director of the Museu Maynense da Academia das Ciências de Lisboa...
.
Material
To date, the most complete specimen of L. antunesi found is a partial skeletonSkeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...
. The holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
, ML 370, consists of the remains of six cervical vertebrae with six ribs, five sacral vertebrae with ribs, 14 caudal vertebrae, eight chevrons, both femora, right tibia and fibula, one metatarsus, two ilia and both pubes and ischia, as well as an associated 32 gastroliths.
A femur (ML 555) found at Porto das Barcas (Lourinhã Formation
Lourinhã Formation
The Lourinhã Formation is a geological formation in West Portugal, named for the municipality of Lourinhã, from which a wide array of fossils comes...
; Late Jurassic) has also been referred to L. antunesi.
Besides these specimens, around 100 eggs (specimen number ML 565), some of them containing embryonic bones, have been found in 1993 at the nearby beach of Paimogo. These were soon assigned to L. antunesi.
Both the skeleton and the eggs are on display at Museu da Lourinhã
Museu da Lourinhã
Museu da Lourinhã is a museum in the town of Lourinhã, west Portugal. It was founded in 1984 by GEAL - Grupo de Etnologia e Arqueologia da Lourinhã ....
.
Systematics
Relationships of Lourinhanosaurus have been uncertain, and no firm consensus has been reached as to its relationships. Initially regarded as a primitive member of AllosauroideaAllosauroidea
Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Sinraptoridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae...
, it was later discussed as being closely related to Sinraptoridae
Sinraptoridae
Sinraptorids were a family of carnivorous theropod dinosaurs. They tended to be large predators, some growing to sizes of . Sinraptorids are carnosaurs, and many were initially classified within Megalosauridae or Allosauridae prior to recent analysis...
, a more inclusive clade within Allosauroidea. Recently, some researchers have been favourable to the idea that L. antunesi is not even an allosauroid, but in fact a member of Megalosauroidea
Megalosauroidea
Megalosauroidea is a group of tetanuran theropod dinosaurs that lived from the Middle Jurassic to the Late Cretaceous period.-Classification:...
, a more primitive group of tetanuran
Tetanurae
Tetanurae, or "stiff tails", is a clade that includes most theropod dinosaurs, as well as birds. Tetanurans first appear during the early or middle Jurassic Period.-Definition:...
theropods. Benson et al. (2010) found it and Poekilopleuron
Poekilopleuron
Poekilopleuron is an extinct genus of large basal tetanuran theropod dinosaur, perhaps belonging to the clade Allosauroidea. It measured 9 metres long and 1 ton in mass...
to belong to Sinraptoridae
Sinraptoridae
Sinraptorids were a family of carnivorous theropod dinosaurs. They tended to be large predators, some growing to sizes of . Sinraptorids are carnosaurs, and many were initially classified within Megalosauridae or Allosauridae prior to recent analysis...
.
Paleobiology
L. antunesi was a rather large carnivorous dinosaur. The specimen found was a sub-adult, measuring some 4.5 m in length and weighting around 160 kg. A full grown adult would have reached 8 meters, taking 10 years to reach that size.Though gastroliths have been found in other theropods since the description of L. antunesi, this was the first theropod dinosaur for which this kind of remains have been assigned. It was concluded during the description that these stones belonged to the animal, and were not swallowed while eating an herbivorous dinosaur.
Dinosaur eggs and embryos, believed to be those of Lourinhanosaurus, have also been discovered; a nest containing more than 100 eggs, some with well-preserved embyros, was announced in 1998.